Full backup will backup all the data on the drive. So, we always make a full backup after we install the system. But the data will be increased, so we have to backup data after a period of time. However, full backup will storage the backed up files again, so that it will take a lot of time and occupy more space. Thus, it is no need to make full backup except the first backup.
I'm very curious about that why you make a full backup and incremental backup at the same time. I think maybe there isn't any trouble with the scheduled because the [url=http://www.backup-utility.com/features/incremental-differential-backup.html]incremental backup[/url] is based on the full backup.